Incidence and seasonal distribution of methicillin-resistant Staphylococcus aureus in adult outpatients at a clinic in Buenos Aires province: period 2006 to 2011

Oct 2012

[Article in Spanish]

Verón MT, Ojeda MG, Avino F, Spelzzini A, Barboza AL, Petrozzino Y.

Source

Servicio de Infectología y Microbiología Clínica, Clínica Privada Independencia. Luis María Drago 5681 (1605) Munro, Provincia de Buenos Aires, Argentina. E-mail: mtveron@gmail.com.

Abstract

In the last decade there was a significant growth of community-acquired methicillin-resistant Staphylococcus aureus(ca-MrSa). We herein describe the annual incidence, seasonal distribution, antimicrobial resistance and phenotypes of MrSain adult outpatients. From january 2006 to december 2011, 173 strains of S. aureus were studied, 77 (45 %) of which wereMrSa. The annual incidence per 100 processed materials increased from 0.13 in 2006 to 0.62 in 2011 due to the oxacillin-resistant phenotype, showing peaks in springsummer until december 2008 and subsequent peaks in autumn-winter. The antimicrobial resistance profile was: erythromycin 24 (31 %), clindamycin 22 (29 %), gentamicin 23 (30 %), ciprofloxacin 13 (17 %), trimethoprim-sulfamethoxazole 3 (4 %), chloramphenicol 2 (3 %), rifampicin 2 (3 %), and minocycline 0. Sixteen phenotypes were identified; the oxacillin-resistant phenotype being the most common, accounting for 53 % (41 isolates) and exhibiting an increase ranging from 31 % to 65 %. The empirical treatment of infections was changed and prevention measures were implemented among contacts.

PubMed

Genotypes, exotoxin gene content and antimicrobial resistance in Staphylococcus aureus recovered from foods and food-handlers.

Feb 2012

Argudín MA, Mendoza MC, González-Hevia MA, Bances M, Guerra B, Rodicio MR.

Source

Department of Functional Biology, Microbiology Area, University of Oviedo. Julian Clavería 6, 33006 Oviedo, Spain.

Abstract

Staphylococcal food poisoning, one of the most common food-borne diseases, results from ingestion of one or more staphylococcal enterotoxins (SEs) performed by Staphylococcus aureus in foods. In the present study, 64 S. aureusisolates recovered from foods and food handlers, associated or not with food-poisoning outbreaks in Spain, were investigated. They were assigned to 31 strains by spa typing, MLST, exotoxin gene content, and antimicrobial resistance. The strains belonged to ten clonal complexes (CCs): CC5 (29.0%), CC30 (25.8%), CC45 (16.1%), CC8, CC15 (two strains each), CC1, CC22, CC25, CC59, and CC121 (one each). They contained haemolysin genes (90.3%); lukED (77.4%); exfoliatin genes: eta, etd (6.5% each) and etb (3.2%); tst (25.8%); and enterotoxin or enterotoxin-like genes or clusters: sea (38.7%), seb (12.9%), sec (16.1%), sed-selj±ser (22.9%), selk-selq (6.5%), seh, sell, selp (9.7% each), egc1 (32.3%), and egc2 (48.4%). The number of se/sel genes ranged from 0 to 12. All isolates carrying tst, and most isolates with genes encoding classical enterotoxins (SEA, SEB, SEC and SED), expressed the corresponding toxin(s). Two CC5 isolates from hamburgers (t002/ST5, t2173/ST5) were methicillin resistant and harboured SCCmec IVd. Six (19.4%) were mupirocin resistant and one (t120/ST15) from a food handler carried mupA (MIC 1250 μg/ml). Resistances to ampicillin (blaZ; 61.3%), erythromycin (ermA-ermC/ermC; 25.8%), clindamycin (msrA-msrB/msrB; 16.1%), tetracycline (tetK; 3.2%), and amikacin-gentamicin-kanamycin-tobramycin (aacA+aphD-aphA; 6.5%) were also observed.

The presence of S. aureus with an important repertoire of virulence and resistance determinants in the food chain represents a potential health hazard for consumers and deserves further observation.

PubMed